Evaluation of electric pulp test thresholds and correct probe tip placement site in developing incisors: a clinical study in 1200 teeth.

PURPOSE: Although electric pulp tests (EPT) may play a valuable diagnostic role in traumatized immature permanent teeth, the EPT threshold values which can be used as reference are not known. The aim of this study was to determine the average range of EPT threshold values in healthy permanent incisors according to their stage of root development. METHODS: A total of 1200 permanent incisors were examined in 273 children (142 girls, 131 boys) aged 6-12 years. Panoramic radiographs were used to group teeth according to the stage of root development. A digitest II pulp vitality tester (Parkell, Inc, Edgewood, NY) was used along with toothpaste as the conducting medium to determine sensibility on three different sites (incisal, middle and cervical third). RESULTS: In all teeth, mean EPT values showed a tendency to decrease along with advanced root development. Irrespective of the stage of root development, the lowest EPT values were obtained when measurements were made on the incisal third of the crown (p < 0.001). Mandibular incisors had lower mean response thresholds than their maxillary counterparts. CONCLUSION: The present findings provide reference EPT threshold values according to stage of tooth development to monitor the post traumatic pulp status of permanent incisors.

The variability of electric pulp response thresholds in primary molars: a clinical study.

PURPOSE: The variability of the EPT response threshold is the most important part of accurate diagnosis of pulp status of caries-affected resorbing primary teeth. This study evaluated the mean EPT threshold values and appropriate electrode placement sites for primary molar teeth based on their physiological root resorption levels. METHODS: This study was conducted with 100 primary second molars in 100 children ages 3-12 (mean age: 7.88 years). Teeth were divided into 2 groups according to physiological root resorption levels. EPT response thresholds were recorded at the mesiobuccal cusp, occlusal third, middle third and cervical third of the crown. Data were analyzed according to resorption level using one-way analysis of variance and Duncan tests, with the level of significance set at 0.05. RESULTS: Mean threshold values at all placement sites were higher in the group with the higher level of physiological root resorption. In terms of placement, the lowest mean EPT threshold values were obtained at the mesiobuccal cusp regardless of resorption level. CONCLUSIONS: According to the study results, higher resorption levels were associated with higher physiologocial threshold values for EPT of primary second molars, with the mesiobuccal site identified as the most appropriate electrode placement site, regardless of resorption level.

Clinical performance of a glass ionomer sealant protected with two different resin-based agents over a 2-year follow-up period.

AIM: To evaluate the effects of two different resin coating materials on the clinical performance of a conventional glass ionomer sealant. MATERIALS AND METHODS: Permanent first mandibular molars of 60 children aged 6-9 years were sealed with Fuji VII. In each child, G-Coat Plus coating agent was applied to molars on one side and Heliobond coating agent to molars on the opposite side of the mouth. Clinical evaluations were carried out at 1, 6, 12, 18 and 24 months after sealant and coating application. RESULTS: At 1, 6, 12, 18 and 24 months after sealant and coating application, total sealant retention rates were 88%, 40%, 19%, 15% and 9% for molars coated with G-Coat Plus, and 93%, 47%, 17%, 15% and 7% for those coated with Heliobond. The differences between the two coating agents were not statistically significant (p>0.05). No incidence of caries was observed in either group during the two-year evaluation period. STATISTICS: Wilcoxon signed rank test was used to compare differences in retention rates and caries incidence by coating agent. CONCLUSION: Although retention rates of Fuji VII were relatively low and similar for both resin coating agents tested, dental caries were not observed in either group during the 24-month study period. In children with a high risk of caries and partially erupted molars, the use of a glass ionomer sealant with a resin-based coating agent should be encouraged.

Clinical and radiological evaluation of calcium sulfate as direct pulp capping material in primary teeth.

AIM: To evaluate the clinical and radiological response of primary molars to direct pulp capping with calcium sulfate hemihydrate. MATERIALS AND METHODS: Forty primary molar teeth in 40 healthy children aged 5-9 years were treated by direct pulp capping. Teeth were randomly assigned to two groups (n=20) according to material used for capping, as follows: Group 1: calcium hydroxide cement (Dycal); Group 2: calcium sulfate hemihydrate (Dentogen). All teeth were restored with a conventional glass ionomer base (Fuji IX) and amalgam. RESULTS: After 12 months, the overall success rate of direct pulp capping was approximately 75% (24/32 teeth, excluding exfoliations). The success rate did not differ significantly between calcium hydroxide and calcium sulfate hemihydrate treatment. CONCLUSION: Calcium sulfate hemihydrate was found to be as successful as calcium hydroxide for direct pulp capping of primary molars with Class I cavities. Further histological studies are needed to support these findings.

The effects of ovariectomy and naproxen treatment on the strength of femoral midshaft and molar alveolar region in rats / Efectos de la ovariectomía y tratamiento con naproxeno sobre la resistencia de la parte media de la diáfisis femoral y la región alveolar molar en ratas

The goal of the present study was to investigate the effects of ovariectomy and naproxen treatment on both femoral and mandibular bone mass and biomechanical competence. Sprague-Dawley rats were used and divided into five groups: baseline, sham ovariectomized, ovariectomized, sham ovariectomized + naproxen treatment, ovariectomized + naproxen treatment. Mandibles and femurs of the rats were extracted and bone mineral density of the extracted specimens were determined. The volumes and ash weights of the femurs and mandibles were estimated. Maximum loads of the femurs and mandibles were determined by using a three point bending test. Ovariectomy decreased bone mineral density of the femoral midshaft, however naproxen prevented this decrease. Neither ovariectomy nor naproxen treatment affected the BMD in the molar alveolar region. Maximum load was found significantly decreased in the femoral midshaft, however, naproxen treatment prevented this decrease. Maximum load of the molar alveolar region did not significantly change. Naproxen prevents the strength characteristics of femoral midshaft afforded by ovariectomy. However, neither ovariectomy nor naproxen has an effect on the molar alveolar region of the mandible.

El objetivo del presente estudio fue investigar los efectos de la ovariectomía y el tratamiento con naproxeno sobre la masa y la competencia biomecánica del fémur y hueso mandibular. Fueron utilizadas ratas Sprague-Dawley, la que se dividieron en cinco grupos: referencia, ovariectomizadas simuladas, ovariectomizadas, ovariectomizadas simuladas + tratamiento naproxeno, ovariectomizadas + tratamiento naproxeno. Las mandíbulas y los fémures de las ratas fueron extraídos y se determinó la densidad mineral ósea (DMO) de las muestras extraídas. Los volúmenes y pesos de la ceniza fueron estimados. Las cargas máximas de las mandíbulas y fémures se determinaron utilizando un ensayo de flexión de tres puntos. La ovariectomía disminuyó la densidad mineral ósea de la diáfisis media del fémur; sin embargo, el naproxeno impidió esta disminución. Ninguna ovariectomía sin tratamiento de naproxeno afectó a la DMO en la región alveolar molar. La carga máxima se encontró significativamente disminuida en las diáfisis femoral media, pero por el tratamiento de naproxeno no se produjo esta disminución. La carga máxima de la región alveolar molar no cambió en ninguna condición. El naproxeno previene los cambios de resistencia causados por la ovariectomía de la diáfisis media del fémur. Sin embargo, ni la ovariectomía ni el naproxeno tienen un efecto en la región alveolar molar de la mandíbula.